1. Field of the Invention
This invention is generally directed to automated medication dispensers which are programmable to make medication available to patients on a predetermined schedule over an extended period of time and, more specifically, to such dispensers which include a plurality of containers containing medicine to be taken and which containers are carried by an indexing assembly so as to be moved relative to a dispenser outlet on a predetermined schedule. The invention is further directed to dispensers which are portable and electrically operated and which may include a battery backup system for insuring fail-safe operation during a loss of conventional power. The dispensers further include tamper-resistant mechanisms for preventing unauthorized movement of the indexing assembler to prevent untimely access to medications.
2. History of the Related Art
There are many patients who must take one or more medications over a period of time. Frequently, patients will require multiple dosages of different medicines in a single day with the medications being required at predetermined time intervals. To be effective, many medications must be taken at predetermined times over a period of days, weeks or longer. Therefore, it is extremely important to the health and welfare of patients that they follow their medication schedule to insure the optimum benefit to be obtained from their medication.
In clinics and hospitals, doctors and nurses maintain timing schedules for patients and must take steps to insure that each patient receives the proper medication at the proper times. Such a labor intensive system for insuring that patients take their required medication at the proper time greatly affects the cost of providing medical care. There are, of course, circumstances wherein patients may not be capable of taking medication at proper times and thus require direct assistance. However, there are many instances, both in clinic and hospital environments as well as where patients are receiving medication on an out-treatment basis, where patients have the physical ability to take a medication if they are aware that a medicinal dosage is required at a specific time.
Over the years, there have been many dispensers designed to facilitate the proper administration of medicine to patients who require that medications be taken at specific times over a prolonged period. Basic dispensers included containers having a plurality of separate receptacles for receiving predetermined medications. For example, a container may include seven receptacles each representing a day of the week. Medication is placed within the receptacles with each receptacle being marked with a day of the week. The patient is directed to take the prescribed medicine from the proper receptacle on a predetermined schedule.
Such prior art mechanical dispensers which require that the patient take medications on a prescribed basis have not proven to be satisfactory. Often, patients forget to take their medication or to take their medication in a timely manner. Such failure to take medication when due not only results in the ineffective administration of the medication, but frequently patients will attempt to make up for missed dosages by taking several dosages at a later time which can be hazardous to the patient""s health.
To prevent patients from taking missed dosages at a later time, some prior art dispensers have been designed to incorporate motors or drive mechanisms for indexing a receptacle or compartments in which medications are contained away from a dispensing outlet. Such dispensers are operable to move a compartment in alignment with a dispensing outlet only at a predetermined time. If a medication has not been removed from the dispenser within a predetermined time, the medication is moved from the dispensing outlet. Unfortunately, many prior art dispensers can be easily tampered with, thereby allowing a patient to obtain access to medicines which should not be taken.
To alert patients that medication is required, some prior art dispensers have been designed to incorporate audible or visual signal devices for indicating a time for a medicine to be taken. For instance, such dispensers may incorporate a buzzer which sounds for a period of time to alert a patient that medication is required. Such signaling devices are more effective in assuring that a patient follows a predetermined medication schedule, however such devices do not prevent a patient from doubling up on dosages which have been missed for one reason or another.
Some examples of prior art medication dispensers which provide for alarms or signals and which are designed for dispensing medication over a period of time and which also include programmable timers include U.S. Pat. No. 4,207,992 to Brown, U.S. Pat. No. 4,911,327 to Shepherd et. al., U.S. Pat. No. 5,176,285 to Shaw, U.S. Pat. No. 5,323,929 to Marlar, U.S. Pat. No. 5,412,372 to Parkhurst et. al., and U.S. Pat. No. 5,609,268 to Shaw.
The present invention is directed to a portable and tamper resistant electronically operated medication dispenser which incorporates a programmable timer and drive assembly for selectively indexing a plurality of separate containers relative to a dispenser outlet. In the preferred embodiment, the present invention includes a portable carrying case which may be locked to prevent access to the interior. Within the carrying case is an indexing drive wheel and a dispenser wheel having a plurality of vertically aligned and spaced openings therein, each being of a size to selectively receive a container. In the preferred embodiment, there are two circular series of openings in each wheel. The containers are configured to receive required dosages of medicine which a patient must take and which are normally filled by competent medical technicians, such as physicians or nurses. The indexing drive wheel and dispenser wheel are designed to permit controlled dispensing of medications over a period of a week with a separate section of the wheels being available to contain or support medication for an additional day in the event of an emergency. Further, in the preferred embodiment, a plurality of openings are provided for each day so that containers of medication may be indexed in a timely manner at up to six or more intervals during a given day. Utilizing the controller associated with the invention, the indexing wheel and dispenser wheel can be selectively moved so that doses of medicine are supplied at varied intervals for each day of the week the dispenser is in use.
The movement of the ratchet wheel of the present invention is accomplished by a motor connected to a rotary indexing drive mechanism which includes at least two driver pins which are offset to the rotary drive axis of the drive mechanism. The pins are spaced such that when one or a first pin seats within one of a plurality of equally spaced slots which are formed in the outer periphery of the drive wheel and the indexing drive mechanism is not activated, the other or second pin is spaced from the periphery of the drive wheel with the drive wheel being locked from rotation by the first pin. Upon activation of the motor, the drive mechanism rotates 180xc2x0. During this rotation, the first pin moves the drive wheel about its axis of rotation as the second pin enters the next slot in the periphery of the drive wheel. In this manner, the dispenser wheel is indexed one position such that the next opening for a medicine container is moved into alignment with the dispenser outlet.
Mounted within the dispenser adjacent to the dispenser opening are first and second switches which are engageable by containers which are being indexed into alignment with the dispenser outlet. The switches are electrically connected to sound an audible alarm that sounds when a container moves into alignment with the dispenser opening. In some embodiments, a timer in the main control assembly will cause the alarm to sound for a predetermined period. The container contact switches adjacent the dispenser outlet are also connected to activate a visual signal such as a light on the dispenser case. Upon removal of the container by a patient, the container contact switches are opened and the light and sound deactivated. Therefore, with the present invention, a visual and or sound signal that medication is required remains as long as a medication container is aligned with the dispenser outlet.
Access to a container which has been moved into alignment with the dispenser outlet is controlled by a automatically controlled closure member which is pivotally mounted to move from a first position closing the outlet to a second position opening the outlet whenever a medication container is in one of the inner or outer series of openings. The closure member is connected to a crank arm assembly driven by a motor. The crank assembly is connected to a double cam which controls a pair of switches to terminate power to the motor after the crank assembly has moved the closure member to an open or closed position. The operation of the closure control motor is in response to a container contacting one of the container contact switches. Once the closure member is moved to the open position, all power to the motor is stopped for a predetermined period of time to allow a patient to remove a medication container. Thereafter, the control unit reactivates the motor and the crank assembly moves the closure member to the closed position. A slot is provided in one arm of the crank assembly to prevent closure of the closure member by allowing relative movement in the components of the crank assembly in the event a person""s fingers or other obstructions is within the outlet when the closure member is being closed. A spring or other resilient element connected to the closure member will complete the closing movement of the closure member once the obstruction has been removed. Once the closure member reaches the fully closed position, the slotted arm of the crank assembly drops down off a ledge on an upper cam driven by the motor, locking it into the closed position, preventing the closure member from being pried open.
The drive wheel indexing assembly further functions as a brake mechanism which restricts movement of the drive wheel such that a patient cannot move the dispenser wheel and obtain access to medication with exception of those medications which are contained within a container aligned with the dispenser outlet.
The present invention further incorporates a rechargeable battery which will permit operation of the dispenser in the event of a power failure or when there is no AC power source. The carrying case is also designed to store containers which are to be used.
It is a primary object of the present invention to provide a portable electrically operated medication dispenser which prevents unauthorized access to medication contained therein and which incorporates a mechanism for resisting tampering with the normal operation of the dispenser such that medication cannot be obtained by a patient or other individual until the medication is aligned with a dispenser outlet at a predetermined time.
It is also an object of the present invention to provide a medication dispenser which is portable and which is designed to allow its use with a conventional source of electrical power such as an AC power source but which is also capable of functioning in the event of loss of AC power by power from a rechargeable battery.
It is yet another object of the present invention to provide a medication dispenser which permits the controlled dispensing of a plurality of different medications, such as tablets and capsules and the like which must be taken by a patient at different periods of a day, and which can be used for a period in excess of a week under normal circumstances.
It is a further object of the present invention to provide a portable medication dispenser which includes a programmable controller for allowing medication to be dispensed at any given time over a period of a week or more such that dosages may be provided to a patient on a predetermined schedule.
It is also an object of the present invention to provide a medication dispenser which includes a plurality of sterilized containers for receiving different medications and which containers are appropriately retained in a dispensing mechanism in such a manner that the medication is made available to a patient on a predetermined schedule by entry of a sequenced timing program into a programmable timer or controller.
It is yet another object of the present invention to provide a medication dispenser for dispensing medications which must be administered to a patient in a predetermined time sequence and wherein access to the medications is controlled to prevent doubling of dosages in the event a patient does not take a medication within a predetermined period of time.